USPTO Patents Application 10054241

01/29/2004 17:42 7814019966

DCM

PAGE 03/20

Application No.: 10/054,241 Attorney Docket No.: EMC2-078AUS

Supplemental Response

Amendments to the Claims

This listing of claims will replace all prior versions, and listings, of claims in the
application.

Listing of Claims:
Claims 1-10 (cancelled)

11. (previously presented) A data storage system wherein end-user data is transferred between a
host computer and a bank of disk drives through an interface, such interface, comprising:

a memory;

a plurality of directors, at least one front-end one of the directors being in communication
with the host computer and at least one rear-end one of the directors being in communication
with the bank of disk drives, each one of the directors comprising:

a central processing unit;

an interface state data bus section, for carrying interface state data, such interface
state data bus section being in communication with both:

(a) the at least one front-end one and the at least one rear-end one of the
directors; and

(b) the memory;

a plurality of end-user data busses, for carrying end-user data, each one of the plurality of
end-user data busses having a first end coupled to a corresponding one of the plurality of
directors and a second end coupled to the memory; and

wherein the central processing units of such plurality of di rectors control the end-user
data transfer between the host computer and the bank of disk drives through the memory via the
end-user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors via the interface state data bus section.

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Application No.; 10/054,241 Attorney Docket No.: EMC2-078AUS

Supplemental Response

12. (previously presented) The system recited in claim 1 1 wherein the end-users data busses are
serial busses.

13. (previously presented)The system recited in claim 1 1 wherein the interface state data bus
section includes parallel busses.

14. (previously presented)The system recited in claim 13 wherein the paraJlel busses are coupled
to the directors in a multi-drop configuration.

15. (previously presented)The system recited in claim 13 wherein the end-user data busses are
serial busses.

16. (previously presented)The system recited in claim 15 wherein the parallel busses are coupled
to the directors in a multi-drop configuration.

17. (presently amended)The system recited in claim 1 1 including a coupling node and wherein
each the memory has a plurality of regions and wherein the each one of the end-user data buses
is coupled to the plurality of regions selectively through the_coupling node, j

18. (previously presented)The system recited in claim 17 wherein the coupling node includes a
cross-bar switch.

19. (presently amended) The system recited in claim 13 wherein the interface state data bus
section includes a plurality of parallel busses, each one thereof being coupled to a-one of the |
plurality of directors and to the memory.

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Application No.: 10/054,241 Attorney Docket No.: EMC2-078AUS

Supplemental Response

20. (previously presented) A method of operating a data storage system wherein end-user data is
transferred between a host computer and a bank of disk drives through an interface, such method
comprising:

providing a memory;

providing a plurality of directors, each one of the directors having a central
processing unit, at least one front-end on e of the directors being in communication with the host
computer and at least one rear-end one of the directors being in communication with the bank of
disk drives;

providing a plurality of interface state data busses for carrying interface state data,
such interface state data busses being in communication with both:

(a) the at least one front-end one and the at least one rear-end one of the directors;

and

(b) the memory;

providing a plurality of end-user data busses, for carrying end-user data, each one of
the plurality of end-user data busses having a first end coupled to a corresponding one of the
plurality of directors and a second end coupled to the memory; and

wherein the central processing units of such plurality of directors control the end-user
data transfer between the host computer and the bank of disk drives through the memory via the
end-user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors via the interface state data bus.

21. (previously presented) A data storage system wherein end-user data is transferred between a
host computer and a bank of disk drives through an interface, such interface, comprising:

a memory;

a plurality of directors, each one having a central processing unit, at least one front-
end one of the directors being in communication with the host computer and at least one rear-end
one of the directors being in communication with the bank of disk drives;

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Application No.: 10/054,241 Attorney Docket No. : EMC2-078 AUS

Supplemental Response

an interface state data bus section, for carrying interface state data, such interface
state data bus section being in communication with the at least one front-end one and the at least
one rear-end one of the directors;

a plurality of end-user data busses, for carrying end-user data, each one of the
plurality of end-user data busses having a first end coupled to a coiTesponding one of the
plurality of directors and a second end coupled to the memory; and

wherein such central processing units of the plurality of directors control the end-
user data transfer between the host computer and the bank of disk drives via the end-user data
busses in response to interface state data generated by the directors, such generated interface
state data being transferred among the directors via the interface state data bus section.

22. (previously presented)The system recited in claim 21 wherein the end-user$ data busses are
serial busses.

23. (previously presented)The system recited in claim 21 wherein the interface state data bus
section includes parallel busses.

24. (previously presented)The system recited in claim 23 wherein the parallel busses are coupled
to the directors in a multi-drop configuration.

25. (previously presented)The system recited in claim 23 wherein the end-user data busses are
serial busses.

26. (previously presented)The system recited in claim 25 wherein the parallel busses are coupled
to the directors in a multi-drop configuration.

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Application No.: 10/054,241

Attorney Docket No.: EMC2-078AUS

Supplemental Response

27. (presently amended) The system recited in claim 21 including a coupling node and wherein
each the memory has a plurality of regions and wherein the each one of the end-user data buses
is coupled to the plurality of regions selectively through jhe coupling node.

28. (presently amended) The system recited in claim 23 wherein the interface state data bus
section includes a plurality of parallel busses, each one thereof being coupled tq a one of the
plurality of directors and to the memory.

29. (currently amended) A method of operating a data storage system wherein end-user data is
transferred between a host computer and a bank of disk drives through an interface, such method
comprising:

providing a memory;

providing a plurality of directors each one of the directors having a central processing

unit, at least one front-end one of the directors being in communication with the host computer
and at least one rear-end one of the directors being in communication with the bank of disk
drives;

interface state data section being in communication with the at least one front-end one and the at
least one rear-end one of the directors,

providing a plurality of end-user data busses, for carrying end -user data, each one of

the plurality of end-user data busses having a first end coupled to a corresponding one of the
plurality of directors and a second end coupled to the memory; and

wherein $uch central processing units of the plurality of directors control the end-user

data transfer between the host computer and the bank of disk drives and the memory via the end-
user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors.

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providing an interface state data section for carrying interface state data, such

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Supplemental Response

30. (previously presented) A data storage system wherein end-user data is transferred between a
host computer and a bank of disk drives through an interface, such interface, comprising:

a memory;

a plurality of directors, each one thereof having a central processing unit, a front-end
portion of such plurality of directors being in communication with the host computer, and a rear
end portion of such plurality of directors being in communication with the bank of disk drives;

an interface state data bus section, for carrying interface state data, such interface
state data bus section being in communication with both the front-end portion of the plurality of
directors and the rear end portion of the plurality of directors;

a plurality of end-user data busses, for carrying end-user data, each one of the
plurality of end-user data busses having a first end coupled to a corresponding one of the
plurality of directors and a second end coupled to the memory; and

wherein the central processing units of such plurality of directors control the end-user
data transfer between the host computer and the bank of disk drives through the memory via the
end-user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors.

31. (previously presented) The system recited in claim 30 wherein the end-users data busses are
serial busses.

32. (previously presented) The system recited in claim 30 wherein the interface state data bus
section includes parallel busses.

33. (previously presented) The system recited in claim 32 wherein the parallel busses are coupled
to the directors in a multi-drop configuration.

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Supplemental Response

34. (previously presented) The system recited in claim 32 wherein the end-user data busses are
serial busses.

35. (previously presented) The system recited in claim 34 wherein the parallel busses are coupled
to the directors in a multi-drop configuration.

36. (presently amended) The system recited in claim 30 including a coupling node and wherein
each the memory has a plurality of regions and wherein the each one of the end-user data buses
is coupled to the plurality of regions selectively through the coupling node. |

37. (previously presented) The system recited in claim 36 wherein the coupling node includes a
cross-bar switch.

38. (presently amended) The system recited in claim 32 wherein the interface state data bus
section includes a plurality of parallel busses, each one thereof being coupled to a one of the j
plurality of directors and to the memory.

39. (previously amended) A method of operating a data storage system wherein end-user data is
transferred between a host computer and a bank of disk drives through an interface, such method
comprising:

providing a memory;

providing a plurality of directors, each one of the directors having a central
processing unit, a front end portion of the directors being in communication with the host
computer and a rear end portion of the directors being in communication with the bank of disk
drives;

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Supplemental Response

providing an interface state data section for carrying interface state data, such
interface state data section being in communication with the front end portion of the directors
and the rear end portion of the directors,

providing a plurality of end-user data busses, for carrying end-user data, each one of
the plurality of end-user data busses having a first end coupled to a corresponding one of the
plurality of directors and a second end coupled to the memory; and

wherein the central processing units of such plurality of directors control the end-user
data transfer between the host computer and the bank of disk drives and the memory via the end-
user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors.

40. (presently amended) A data storage system wherein end-user data is transferred between a
host computer and a bank of disk drives through an interface, such interface, comprising:

a memory;

a plurality of directors, comprising:

a plurality of front-end directors, each one of such front-end direcytors flrgsters
having a central processing unit, such plurality of front end directors being in communication
with the host computer, and

a plurality of rear end directors, each one of the rear-end directors having a central
processing unit, such plurality of rear end directors being in communication with the bank of
disk drives;

an interface state data bus section, for carrying interface state data, such interface
state data bus section being in communication with both the front-end portion of the plurality of
directors and the rear end portion of the plurality of directors;

a plurality of end-user data busses, for carrying end-user data, each one of a first
portion of the plurality of end-user data busses having a first end coupled to a corresponding one
of the plurality of front end directors and a second end coupled to the memory and each one of a
second portion of the plurality of end user data buses having a first end coupled to a

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Application No.: 10/054,241 Attorney Docket No.: EMC2^078AUS

Supplemental Response

corresponding one of the plurality of rear end directors and a second end coupled to the memory;
and

wherein the central processing units of such plurality of directors control the end-user
data transfer between the host computer and the bank of disk drives through the memory via the
end-user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors.

41. (previously presented) The system recited in claim 40 wherein the first portion of the end-
users data busses comprises a plurality of serial busses.

42. (previously presented) The system recited in claim 40 wherein the second portion of the
interface state data bus section comprises a plurality of serial busses.

43. (previously presented) The system recited in claim 42 wherein the first portion of the end-
users data busses comprises a plurality of serial busses,

44. (previously amended) A method of operating a data storage system wherein end-user data is
transferred between a host computer and a bank of disk drives through an interface, such method
comprising:

providing a memory;

providing a plurality of directors, such plurality of directors comprising:

a plurality of front end directors, each one thereof having a central processing unit,
such plurality of front end directors being in communication with the host computer, and;

a plurality of rear end directors, each one thereof having a central processing unit,
such plurality of rear end directors being in communication with the bank of disk drives;

providing an interface state data section for carrying interface state data, such
interface state data section being in communication with the plurality of front end directors and
the plurality of rear end directors;

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Supplemental Response

providing a plurality of end-user data busses, for carrying end-user data, each one of a
first portion of the plurality of end-user data busses having a first end coupled to a corresponding
one of the plurality of front end directors and a second end coupl ed to the memory and each one
of a second portion of the plurality of end user buses having a first end coupled to a
corresponding one of the plurality of the rear end directors and a second end coupled to the
memory;

wherein the central processing units of such plurality of directors control the end-user
data transfer between the host computer and the bank of disk drives and the memory via the end-
user data busses in response to interface state data generated by the directors, such generated
interface state data being transferred among the directors.

45. (previously presented) The method recited in claim 44 wherein the first portion of the end-
users data busses is provided with a plurality of serial busses.

46. (previously presented) The method recited in claim 44 wherein the second portion of the
interface state data bus section is provided with a plurality of serial busses.

47. (presently amended) The method recited in claim 46 wherein the first portion of the end-
users data busses is provided with a plurality of serial busses.

48. (previously presented) (previously presented) A system, comprising;
a plurality of directors, each one of the directors having;

a plurali ty of fl -end user data ports and an interface state data port; jmd
a crossbar switch having a p1urality_of first ports a nd a plurality of second ports,
each one of the Cja SSkgLSM^
plurality of end user data ports;
a cache memory having a plurality of memory sections:

wherein each one of the crossba r switch second ports is coupled to a corresponding one
of the plurality of memory sections coupled to the end user data ports of the plurality of
dir e ctors ;

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Supplemental Response

wherein the directors control end user data transfer with end user data in such end user data
transfer passing through the cache memory in response to interface state data passing through the
interface state data ports of the directors.

49. (presently amended) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising:

a plurality of first directors coupled to host computer/server, each one of the first
directors having:

-a ftft -plur a litv of end user data ports and an interface state data port;_and
a crossbar switchjiaying^a pluralifanpf first ports and a plurality of second ports.

each one of the crossbar switch first port sJse ing co u pled to a corresponding one of the

pluralityof end user data ports;

a plurality of second directors coupled to the bank of disk drives, each one of the second
directors having;

an- a plurality of end user data port and an interface state data port; ja&d

a plurality of end user data ports and a interface state data port: and

a crossbar switch haying a p[^ plurali t y of second ports.

each one of the crossbar switch first ports being coupled toaeorresponding one of the

plurality of end user data ports,:

a cache memory having a plurality of memory sections:

wherein each_pne of the crossbar switch second ports of the first and second directors
being is coupled to a corresponding one of the plurality of memory sectionseoupted-to-the end
user data port s of th e plurality of first dir e ctors and oecond directors ;

wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through the cache memory in response to interface state data passing between the first director and
the second director through the interface state data ports of the plurality of first directors and the
plurality of second directors.

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Supplemental Response

50. (presently amended) A system, comprising:
a plurality of directors, each one of the directors having:

a-plurality of a-end user data ports, and an interface state data portand
a crossbar switch having a plurality of first ports and a plurality of second p orts,
each one of the crossbar switch first ports being crm pled to a corresponding one of the
Plurality of end user data port?;;

±

a cache memor y having a plurality of memory section?;

wher ein each o ne_ofi.be crossbar switch second ports of thejBrg.t,.ai)d second directors
being coupled to is c oupled to a corresponding one of the plurality of memory sections -;

wherein the directors control end user data transfer with end user data in such end user data
transfer passing to the cache memory through the end user data ports in response to interlace state
data passing through the interface state data ports of the directors.

5 1 . (presently amended) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising:

a plurality of first directors coupled to host computer/server, each one of the first
directors having: M r a plurality of end user data ports^-and an interface state data port and a
crj^gjaapw a plurali tyof jfirsLpor ts and a plurality o f se cond ports, each one oLthe_

crossbar switch first ports being coupled to a correspondingjone of the plurality of end user data |
pods;;

a plurality of second directors coupled to the bank of disk drives, each one of the second
directors having: -aft- a plural ity of end user data ports;-&ftd an interface state data port^anda
.qrossbar switch having a p M.t^_o,f first ports and a plurality of sec a nd_ports» each one of the
crossbar switch first p osts being coupled to a corresponding one of the plurality of end user da ta

pom

a cache memor y having a pl ur attty_of memory sections :

wh rem ejacLpnejpf ^ switch second ports of the first and second armors

being is couplgd_to_a corresponding one of the plurality of memory sections; and

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Supplemental Response

wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through the end user data ports in response to interface state data passing between the first director
and the second director through the interface state data ports of the plurality of first directors and the
plurality of second directors.

52 (presently amended) A system, comprising:
a plurality of directot^^cjiqnejbaying a crossbar switch . such cross bar switch having a

plurality ofpocts :

a cache memory having a plur ality of mem ory sections in communication with the
plurality of directors^;

wherein eachone of the plurality of crossbar switch ports of each_one _ pf the plurality af
directors is coupled to a correspondingjme of the plurality of memory sections; and

wherein the directors control end user data transfer with end user data in such data transfer
passing to the cache memory through an end user data communication channel in response to
interface state data passing through the directors through a different, interface state data
communication channel.

53 (presently amended) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising;

a plurality of first directors coupled to host computer/server;
a plurality of second directors coupled to the bank of disk drives;
a cache memory in communication with the plurality of directors, suchjriemory having
memory having a plurality of memory section s;

wherein each one of the plurality of crossbar switch ports of each one of the plurality of
directors is couptedJQ a corresponding one of t he plurality of memorvLsections; and

wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through an end user communication channel in response to interface state data passing between the
first director and the second director through a different, interface state data communication path.

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Supplemental Response

54. (presently amended) A system, comprising:
a plurality of directors, each one of the directors having an end user data port and an

interface state data port, one of such ports being coupled to a crossbar switch;

a cache memory coupled to the end user data ports of the plurality of directors,
wherein the directors control end user data transfer with end user data in such end user data
transfer passing through the cache memory in response to interface state data passing through the
interface state data ports of the directors, such interfa ce state data passing thro ugh a fljfagnt
channel than a channel used to pass the end user data .

55. (presently amended) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising:

a plurality of first directors coupled to host computer/server, each one of the first
directors having an end user data port and an interface state data port; one of such ports being
coupled to a crossbar switch

a plurality of second directors coupled to the bank of disk drives, each one of the second
directors having an end user data port and an interface state data port, one of such ports being
coupled to a crossbar switch;

a cache memory coupled to the end user data ports of the plurality of first directors and
second directors;

wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through the cache memory in response to interface state data passing between the first director and
the second director through the interface state data ports of the plurality of first directors and the
plurality of second direaors,_^chj^terface state^aia passing through a diffe rent ch annel than a
channel used t o pass the end user data .

56. (presently amended) A system, comprising:
a plurality of directors, each one of the directors having a n end user data port and an

interface state data port, one of such ports being coupled to a crossbar switch;
a cache memory ;

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Supplemental Response

wherein the directors control end user data transfer with end user data in such end user data
transfer passing to the cache memory through the end user data ports in response to interface state
data passing through the interface state data ports of the directors, such interface state data passing
through a different channel than a channel .us e d to pass the end us er data.

57. (presently amended) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising:

a plurality of first directors coupled to host computer/server, each one of the first
directors having an end user data port and an interface state data port, one of such ports being
coupled to a crossbar switch;

a plurality of second directors coupled to the bank of disk drives, each one of the second
directors having an end user data port and an interface state data port, one of such ports being
coupled to a crossbar switch;
a cache memory;

wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through the end user data ports in response to interface state data passing between the first director
and the second director through the interface state data ports of the plurality of first directors and the
plurality of second directors , such interface state data passing through a different channel than_a
channel used to pass the end user data .

58. (previously presented) A system, comprising:
a plurality of directors;

a cache memory in communication with the plurality of directors,
wherein the directors control end user data transfer with end user data in such data transfer
passing to the cache memory through an end user data communication channel in response to
interface stale data passing through the directors through a different, interface state data
communication channel, one of such channels being coupled to a crossbar switch.

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Application No.: 10/054,241 Attorney Docket No.: EMC2-078AUS

Supplemental Response

59. (previously presented) A data storage system for transferring data between a host
computer/server and a bank of disk drives through a system interface, such system interface
comprising:

a plurality of first directors coupled to host computer/server;
a plurality of second directors coupled to the bank of disk drives;
a cache memory in communication with the plurality of directors,
wherein the first and second directors control end user data transfer between the host
computer and the bank of disk drives with end user data in such end user data transfer passing
through an end user communication channel in response to interface state data passing between the
first director and the second director through a different, interface state data communication channel
one of such channels being coupled to a crossbar switch.

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